my TT .46 Pro has developed some kind of rust, or rust-colored pigment, on it. its most noticable on the exhaust manifold and in between the fins on the heat sink. anyone had this kind of thing happen? is this normal? how can i get rid of it?

Thanks!

John

Depending on what fuel you are running its probably castor oil varnish.

If your worried about it take the engine apart and remove any rubber seals and the carb and stick it and the muffler in a crock pot with anti freeze over night on low. Use one your not planning to cook in again.

Dry it off and oil the bearings with ATF or something similar and put it back together.

Yup...its probably fuel residue...which is perfectly normal

It's cooked fuel residue -- don't worry about it.

Model airplane fuel is around 70% or more methanol which is highly hygroscopic (absorbs moisture). You can demonstrate this to yourself on a hot humid day by pouring some of it into a saucer. In short order, the surface will turn cloudy which is the methanol sucking the moisture out of the air. To keep your fuel free of moisture, keep your fuel jug tightly closed and use the red plug that it comes with.

If you're concerned about rust, take the backplate off the engine and peer inside. If you see any red spots, that's rust forming. You don't need to disassemble the engine to stop it. Just hit it with some 3-in-1 oil.

Before you depart the field, to prevent problems with moisture and rust in your engine, pull off the fuel line with your engine running to remove any fuel. You don't need to add any after run oil, which doesn't do any good if any fuel is left in the engine, since the fuel contains lubricant and a residue is left behind.

Finally, one of the dumber idea is to subject your engine to a crockpot bath of antifreeze. I remember when the field geezers came up with this idea it was only to clean the outside of the engine. Now they have gone a step further and taken it apart to let all the pieces stew in this mess (350 degrees for 4 hours?). The inside of your engine isn't the same as the inside of a radiator. Depending on temperature and time, the aluminum parts may discolor. Also all the lubricant will be washed off the bearings and other parts. Mechanical parts need to be treated with respect and clean in special solvents and quickly re-oiled to prevent rust.

To keep your engine clean, cover the carb and exhaust outlet (Tower has rubber covers), and give it a shot of Wal-Mart's Mean Green followed by a hot water bath. Next towel it off and finish with a hair dryer. There is also a product called Demon Clean that works quite well:

http://www.cooperfuels.com/demonclean.htm

Ciao,

Mr Akimoto

Most modern engines have aluminum blocks, the antifreeze doesn't just flow through the radiator.

Mr Akimoto seems to be long on advice, but decidedly short on manners & real-world experience. The problem, so far, is baked-on external fuel residue --- there was no mention of internal "rust".

While his advice re. internal inspection & lubrication is reasonably good, he is out to lunch on the anti-freeze issue. The glycol-based anti-freeze bath is a long-established & quite acceptable method of removing fuel residue -- both inside & out. It is NOT accomlished, as he alledges, by "baking" at 350 deg, or anything close to that. The technique involves "simmering" the dissassembled engine parts in automotive glycol-based anti-freeze, at a temp below the boiling point of the liquid. You can find numerous references to it in various RCU threads.

i think it is just fuel residue... i tried scraping some off with my finger nail and it came off. it was kinda gooey so i concluded it was just some fuel that had splattered on the motor and then boiled away.

thanks for the advice... i was just kind of worried for a second there. i love these boards!

John

Modern cars use aluminum radiators, but obviously the antifreeze flows through both the engine block and radiator. So exactly what point were you trying to make?

Ciao,

Mr Akimoto

First you're short on manners and long on ignorance. If the poster is concerned about external rust, then he is likely worried about if it has gotten inside his engine. He like you is ignorant of how to take of his engine, or he wouldn't be asking his question.

Unlike you who are no more than a critic, I try to answer a question with some depth rather than blurt out a couple of meaningless words. Of course, the basis for your argument is reference to some threads on this board. Also you should learn to recognize sarcasm when you see it. And just how many disassembled engines have you simmered in the crockpot that would give your opinion any weight?

Also the antifreeze bath that you so heartily suppport isn't approved of by OS. I doubt that any other reputable maker would approve of it either. All you're doing is parroting some nonsense you read or heard someplace. Acceptable what a word. This is what you are capable of doing is accepting rather than researching or investigating.

Ciao,

Mr Akimoto

ok.. this thread has taken a turn for the worse.... lets close it for now..

ScienceisCool,
I agree. I think that this subject has been covered now, and this has now involved too much personal attacks now. I'm locking this thread down.

Ken